Slide rail device for vehicle

ABSTRACT

The slide rail device includes a lock release lever which switches a locking mechanism between a slide restriction state and a slide restriction release state by rotating in the vertical direction and includes a rail-incorporated portion positioned between an upper rail and a bottom wall of a lower rail, a rotational contact portion which is formed on an upper surface of the rail-incorporated portion and contacts a roof surface of the upper rail, and a biaser which is installed in the rail-incorporated portion and the upper rail and biases the rotational contact portion toward the roof surface.

RELATED APPLICATION DATA

This is a continuation of International Application No.PCT/JP2011/059402, with an international filing date of Apr. 15, 2011,which is herein incorporated by reference in its entirety.

TECHNICAL FIELD

The present invention relates to a slide rail device for a vehicle whichsupports a seat in a slidable manner.

BACKGROUND ART

As a prior art slide rail device for vehicle, a device is known which isequipped with a left and right pair of lower rails which include aplurality of convex teeth (lock teeth) extending and arranged in aforward/rearward direction and which are fixed to a vehicle interiorfloor, a left and right pair of upper rails which support the seatingportion of a seat and are slidably supported by the left and right pairof lower rails, locking levers which are accommodated in the internalspaces of the upper rails and which are supported by the upper rails tobe rotatable in the vertical direction between a lock position to beengaged with the aforementioned convex teeth and an unlock position torelease the engagement with the convex teeth, wire springs (biaser)which bias and rotate the locking levers toward the lock position, andan operating lever, the rear end of which is fixed to the locking leversand the front end of which projects toward the front of the upper rails.

Therefore, when an occupant applies no operating force to the operatinglever, the slide positions of the seat and the upper rails with respectto the lower rails are maintained since the lock levers which are heldin the lock position by the wire springs are engaged with some of theconvex teeth. On the other hand, upon a passenger operating theoperating lever to rotate the lock levers to the unlock position againstthe biasing force of the wire springs, the lock levers are disengagedfrom the convex teeth to thereby allow the seat and the upper rails toslide with respect to the lower rails.

CITATION LIST Patent Literature

-   PATENT LITERATURE 1: Japanese Unexamined Patent Publication No.    2008-265695

SUMMARY OF THE INVENTION Technical Problem

In the slide rail device for vehicle that has the above describedstructure, both left and right ends of a support shaft (rotationalshaft) fixed to a roof portion of an upper rail are fitted intothrough-holes formed through both left and right walls of the upperrail, and the operating lever is biased to rotate by a wire spring aftera bearing hole formed in the operating lever is rotatably fitted on thesupport shaft.

However, the support shaft, which is a separate member from the upperrail and the operating lever, is required; moreover, the through-holesneed to be formed in the upper rail, and therefore, the number ofcomponents is large and the structure is complicated.

The present invention provides a slide rail device for a vehicle inwhich a lock release lever can be rotatably supported by an upper railwith a simple structure and with a small number of components, eventhough a locking mechanism and the lock release lever are installed inan internal space of the upper rail.

Solution to Problem

A slide rail device for vehicle according to the prevent invention ischaracterized by including a lower rail which extends in aforward/rearward direction; an upper rail which is supported by thelower rail to be slidable in the forward/rearward direction; a lockingmechanism which is provided between the upper rail and the lower railand restricts or releases a restriction on sliding of the upper rail; alock release lever which switches the locking mechanism between a sliderestriction state and a slide restriction release state by rotating in avertical direction and includes a rail-incorporated portion positionedbetween the upper rail and a bottom wall of the lower rail; a rotationalcontact portion which is formed on an upper surface of therail-incorporated portion, contacts a roof surface of the upper rail androtatably supports the lock release lever; and a biaser which isinstalled in the rail-incorporated portion and the upper rail, thebiaser biasing the rotational contact portion toward the roof surface.

It is desirable for the rotational contact portion to include aprotrusion which protrudes upward.

The locking mechanism can include a plurality of lock grooves which areformed in the lower rail and aligned in the forward/rearward direction;and a lock portion which is engaged in any one of the lock grooves whenthe lock release lever is in a lock position and escapes from the lockgroove when the lock release lever is in an unlock position.

The biaser can include a lock spring including the lock portion.

The biaser can be a torsion spring, wherein the torsion spring preventsthe lock release lever from moving forward and rearward relative to theupper rail.

Furthermore, the torsion spring includes a lock portion which is engagedin any one of a plurality of lock grooves formed in the lower rail to bealigned in the forward/rearward direction when the lock release lever ispositioned in a lock position, and the lock portions which escapes fromthe lock groove when the lock release lever is positioned in an unlockposition, and wherein the lock release lever includes a first engagingportion which is engaged with the torsion spring at a portion in thevicinity of the lock portion and a second engaging portion which isengaged with the torsion spring at a portion thereof which deviates fromthe first engaging portion in the forward/rearward direction.

A portion of the rail-incorporated portion can be formed as anarrow-width portion which is smaller in width than the surroundingportion of the rail-incorporated portion, and at least part of thebiaser is positioned in a space formed between the upper rail and bothsides of the narrow-width portion.

Advantageous Effects of the Invention

According to the present invention, the rotation support structure forthe lock release lever with respect to the upper rail has small numberof components and is simple in structure because the upper rail is notprovided with a rotational shaft for rotatably supporting the lockrelease lever.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a side view of a slide seat device when upper rails in anembodiment of the present invention have slid to the front end position;

FIG. 2 is a front perspective view of the slide rail device, viewedobliquely from above;

FIG. 3 is an exploded perspective view of the slide rail device, viewedobliquely from above;

FIG. 4 is an exploded perspective view of the slide rail device with theleft rails omitted, viewed obliquely from below,

FIG. 5 is a sectional view taken along the line V-V shown in FIG. 1;

FIG. 6 is an enlarged perspective view of middle parts of one upper railand a lock spring in a mutually separated state, viewed obliquely frombelow;

FIG. 7 is a perspective view of one upper rail, a lock release lever andthe lock spring in an assembled state, viewed obliquely from below;

FIG. 8 is a side view of one upper rail and the lock release lever and aloop handle in a locked state, wherein only the upper rail is shown as alongitudinal sectional side view;

FIG. 9 is a side view similar to that of FIG. 8 in an unlocked state;

FIG. 10 is an enlarged perspective view of one upper rail and theassociated lower rail in a locked state with an outer side wall of thelower rail, and an upright wall and a locking wall of the upper rail cutout;

FIG. 11 is a schematic side view showing a state where one lock springis in a lock position and another state where the same lock spring is inan unlock position;

FIG. 12 is an enlarged perspective view of the front ends of one upperrail and the associated lock release lever and a rear end of the loophandle, viewed from below;

FIG. 13 is a perspective view of one lock release lever, viewed frombelow;

FIG. 14 is an enlarged exploded perspective view of the front end of onelock release lever, a biasing spring and a rear end of the loop handle;

FIG. 15 is an enlarged perspective view of the front end of one lockrelease lever, the biasing spring and a rear end of the loop handle in amutually combined state;

FIG. 16 is an enlarged longitudinal sectional side view of a rear end ofthe loop handle and the front end of the associated lock release leverwith the biasing spring omitted;

FIG. 17 is a view similar to that of FIG. 16 when the loop handle isdepressed;

FIG. 18 is a view similar to that of FIG. 2 when the rear end of a rightrail unit has moved upward compared with the front end thereof due to acollision of another vehicle with the vehicle equipped with the slideseat device;

FIG. 19 is a view similar to that of FIG. 18 when the rear end of theright rail unit has further moved upward compared with the front endthereof;

FIG. 20 is a perspective view of a modified embodiment of one lockrelease lever, viewed obliquely from above;

FIG. 21 is an enlarged perspective view similar to that of FIG. 12,showing the same lock release lever;

FIG. 22 is a sectional view similar to that of FIG. 5, showing the samelock release lever;

FIG. 23 is a perspective view of another modified embodiment of one lockrelease lever, viewed obliquely from above; and

FIG. 24 is an enlarged bottom view of a portion of yet another modifiedembodiment of one lock release lever in the vicinity of the jointbetween a middle portion and a narrow-width portion of the lock releaselever.

DESCRIPTION OF EMBODIMENTS

An embodiment of the present invention will be hereinafter discussedwith reference to FIGS. 1 through 19. Directions described in thefollowing description are defined based on the directions of arrowsshown in the drawings.

A slide seat device 10 is installed onto a floor board F (see FIG. 1)that constitutes a vehicle interior floor of an automobile (vehicle) notshown in the drawings. Four screw holes (two front and rear left holesand two front and rear right holes) F1 are formed through the floorboard F for one slide seat device 10, and four weld nuts N which arecoaxial with the four screw holes F1 are fixed to a lower surface of thefloor board F at positions corresponding to the four screw holes F1,respectively. In addition, positioning holes F2 are formed through thefloor board F at positions immediately behind the front screw holes F1,respectively. The slide seat device 10 is provided with a slide raildevice 15 that constitutes a lower part of the slide seat device 10, anda seat 11 which is fixed to upper surfaces of the slide rail device 15(upper rails 35).

The detailed structure of the slide rail device 15 will be discussedhereinafter.

The slide rail device 15 is provided, as large components thereof, witha left and right pair of rail units 20 and a loop handle 70 whichconnects the front ends of the left and right rail units 20. The leftand right rail units 20 have the same structure while the loop handle 70has a bilaterally-symmetrical shape, and therefore, the slide raildevice 15 is bilaterally symmetrical as a whole.

The left and right rail units 20 have the structure which will bediscussed hereinafter.

Each rail unit 20 is provided with a lower rail 21 which is placed onthe floor board F. The lower rail 21 is a metal-made channel memberwhich extends in the forward/rearward direction and the top thereof isopen, and is provided with a substantially-horizontal bottom wall 22, aleft and right pair of outer wall portions 23 which extend upward fromthe left and right sides of the bottom wall 22, respectively, and leftand right pair of inner wall portions 24 which extend inward andthereafter downward from the top edges of the left and right pair ofouter wall portions 23, respectively. As shown in FIGS. 3 and 10, etc.,a large number of lock grooves 25 are formed in the lower edges of theleft and right inner walls 24 and are aligned in the forward/rearwarddirection. In addition, as shown in FIG. 4, a pair of bolt insertionholes 22 a are formed through the bottom wall 22 in the vicinity of bothfront and rear ends of the bottom wall 22, respectively, and apositioning hole 22 b is formed through the bottom wall 22 immediatelybehind the front bolt insertion hole 22 a. Two spacers 27 are fixed tothe undersurface of the bottom wall 22 in the vicinity of both front andrear ends thereof, respectively, and through-holes 28 formed through thetwo spacers 27 are coaxial with the bolt insertion holes 22 a,respectively.

A front and rear pair of fixing bolts (fixing members) 30 are insertedinto the front and rear bolt insertion holes 22 a of the bottom wall 22from above, respectively. Each fixing bolt 30 is provided with a head(projection portion) 31 which constitutes the upper end of the fixingbolt 30, a flange 32 which is greater in diameter than the head 31 andthe associated bolt insertion hole 22 a and joined to the lower end ofthe head 31, and a threaded portion 33 which extends downward from alower surface of the flange 32 and is slightly smaller in diameter thanthe associated bolt insertion hole 22 a and through-hole 28.

Each rail unit 20 is provided with an upper rail 35 that is slidable inthe forward/rearward direction with respect to the associated lower rail21. The upper rail 35 is a metal channel member which extends in theforward/rearward direction and the bottom thereof is open, and isprovided with a base 36 (provided with a substantially-horizontal roofportion 36 a and a pair of side wall portions 36 b which extend downwardfrom both left and right sides of the roof portion 36 a) which issubstantially inverted U-shaped in cross section and the internal spaceof which constitutes a lever accommodating groove 37, upright walls 38which extend upward from the side wall portions 36 b except centralportions thereof in the longitudinal direction, and locking walls 39which extend upward from the aforementioned central portions of the sidewall portions 36 b. As shown in FIGS. 3, 4 and 6, etc., four guidegrooves 40 are formed through the lower edges of the left and rightlocking walls 39 and the lower edges of the side walls of the base 36 toextend upward. In addition, as shown in FIGS. 3 and 7, etc., the base 36is provided, in the vicinity of a central portion of the roof portion 36a, with a locking lug 42 which is formed by cutting and raising aportion of the base 36 to extend downward and subsequently rearward, andis provided, on portions of the left and right side wall portions 36 bwhich are positioned slightly in front of central portions of the leftand right side wall portions 36 b, with locking lugs 43 which are formedby cutting and raising portions of the left and right side wall portions36 b to extend inward.

Each rail unit 20 is further provided with a lock release lever 47 and alock spring 63 that are installed in the associated upper rail 35.

The lock release lever 47 is a press-molded product formed from a metalplate and also a metal channel member which extends in theforward/rearward direction and the bottom thereof is open, and isprovided with a base wall 47 d and side walls 51 which extend downwardfrom both left and right side edges of the base wall 47 d. The lockrelease lever 47 has a substantially inverted U-shaped cross sectionover the length thereof, a portion of the lock release lever 47immediately in front of a central portion thereof in the longitudinaldirection thereof constitutes a middle portion 48, the internal space ofwhich forms a receptive depressed portion 48 a, and a portion of thelock release lever 47 immediately behind the middle portion 48 is formedas a narrow-width portion 49 which is narrower in width than portions ofthe lock release lever 47 which are positioned in front and behind thenarrow-width portion 49. In addition, ridges 47 b which are formed onouter side surfaces (outer side surfaces in the vicinity of the jointbetween the middle portion 48 and the narrow-width portion 49) of theleft and right side walls 51 to extend in the vertical direction areformed as R-planes (see FIGS. 3, 4, 8, 9 and 13). As shown in FIGS. 3,4, 8 and 9, a rotational contact protrusion 50 which extends in theleftward/rightward direction is protruded from an upper surface of thelock release lever 47. In addition, spring-hook grooves 52 are formed onlower surfaces of the left and right side walls 51 of the lock releaselever 47 in the vicinity of the rear ends of the left and right sidewalls 51, and a lock-spring catching hole 53 and a lock-spring catchinghole 54 are formed through the base wall 47 d of the lock release lever47. Additionally, ridges 52 a substantially identical in shape to theridges 47 b are formed on the left and right side walls 51 immediatelyin front of the spring-hook grooves 52, respectively (see FIGS. 8, 9 and13). A portion of the lock release lever 47 which is positioned in frontof the middle portion 48 constitutes a connecting portion 55 that isgreater in width than the middle portion 48, and a portion of the lockrelease lever 47 which is positioned behind the connecting portion 55constitutes a rail-incorporated portion 47 a. The lower surface of theroof of the front end of the connecting portion 55 is formed as a flatfront limit portion 56, and a space immediately below the front limitportion 56 constitutes a front allowance space 57. In addition, adepressed portion 58 is formed on the connecting portion 55 at aposition immediately behind the front limit portion 56, and the spacecreated by the depressed portion 58 constitutes a rear allowance space59. Furthermore, substantially-horizontal rear limit lugs 60 (the uppersurfaces of which constitute rear limit portions 60 a) which extend indirections to approach each other are projected from the left and rightlower edges of the depressed portion 58. Furthermore, a combination ofthe front allowance space 57 and the rear allowance space 59 constitutesa connecting space 61.

The lock spring 63 is a substantially bilaterally-symmetrical memberformed by bending a metal wire rod. A pair of front and rear lockportions 64 which extend substantially horizontally outwards are formedon portions of both left and right side portions of the lock spring 63which are positioned slightly behind central portions thereof in thelongitudinal direction, respectively. A portion of the lock spring 63which is positioned behind the lock portions 64 extends obliquelyrearwardly upwards from the lock portions 64 when in a free state, and aportion of the lock spring 63 which is positioned in front of the lockportions 64 extends obliquely forwardly upwards when in a free state.The lock spring 63 is provided at the front end thereof with a left andright pair of front-end locking lugs 65 which project upward, andportions of the lock spring 63 which are positioned immediately behindthe front-end locking lugs 65 constitute lever pressing portions 66.

The rail-incorporated portion 47 a of the lock release lever 47 isaccommodated in the lever accommodating groove 37 of the associatedupper rail 35, and the rotational contact protrusion 50 is in contactwith a roof surface of the base 36 (see a contact portion “A” in FIGS. 8and 9; an interspace is formed between the upper surface of therail-incorporated portion 47 a except the rotational contact protrusion50 and a roof surface of the lever accommodation groove 37). As shown inFIGS. 7 through 9, the rear end of the lock spring 63 is lock-engagedwith the locking lug 42 (see the triangular mark in FIG. 8), portions ofthe lock spring 63 which are slightly in front of the lock portions 64are lock-engaged with the left and right locking lugs 43 (see atriangular mark in FIG. 8), each lock portion 64 is lock-engaged withthe associated guide groove 40 from below, and the left and right pairof front-end locking lugs 65 are inserted into the lock-spring catchinghole 53 from below; moreover, portions of the left and right leverpressing portions 66 in the vicinity of the front ends thereof arelock-engaged with the rear edge of the lock-spring catching hole 53, andthe spring-hook grooves 52 are lock-engaged with portions of the lockspring 63 from above which are positioned between the pair of lockportions 64. Installation of the lock spring 63 to the upper rail 35 andlock release lever 47 in this manner puts the lock spring 63 in a stateof being substantially prevented from moving in the forward/rearwarddirection with respect to the upper rail 35 (the lock spring 63 can movewithin a minute moving range in which the locking engagement between thelock spring 63 and the locking lug 42 is not released and the front-endlocking lugs 65 are prevented from coming out of the lock-springcatching hole 53 or are totally prevented from moving forward orrearward), and left and right portions (front half portions) of the lockspring 63 are respectively positioned in a left and right pair of spacesformed between the side walls 51 of the narrow-width portion 49 and thepair of side wall portions 36 b of the upper rail 35 (see FIG. 7). Inaddition, the lock spring 63 that is accommodated in the leveraccommodation groove 37 produces an upward biasing force (elastic force)by being elastically deformed (see arrows ↑ shown in FIG. 8), andaccordingly, this biasing force causes the rotational contact protrusion50 of the lock release lever 47 to be pressed against the roof portion36 a of the base 36, which allows the lock release lever 47 to rotateabout the rotational contact protrusion 50 (about an imaginary rotationaxis in the leftward/rightward direction) about the contact portion Abetween the roof portion 36 a and the rotational contact protrusion 50,and the lock release lever 47 is held in the lock position shown in FIG.8 when no upward external force is exerted on the connecting portion 55.On the other hand, exerting an upward external force on the connectingportion 55 against the biasing force of the lock spring 63 causes thelock lever 47 to rotate to the unlock position shown in FIG. 9.Thereupon, the spring-hook grooves 52 of the lock release lever 47depresses the portions of the lock spring 63 which are positionedbetween the pair of lock portions 64, so that each lock portion 64escapes downward from the associated guide groove 40 (see FIG. 9 andimaginary lines shown in FIG. 11).

An assembly made by inserting a combination of one upper rail 35, onelock release lever 47 and one lock spring 63, which are combinedtogether in the above described manner, into one lower rail 21 from thefront or rear end opening of the lower rail 21 constitutes one rail unit20. When one rail unit 20 is assembled, the upright walls 38 and thelocking walls 39 of the upper rail 35 enter the spaces formed betweenthe outer wall portions 23 and the inner wall portions 24 as shown inFIG. 5, and a plurality of bearing balls 69 which are rotatablysupported by retainers 68 installed in the aforementioned spaces are inrotatable contact with both outer surfaces of the upright walls 38 andinner surfaces of the outer wall portions 23, which allows the upperrail 35 (and the lock release lever 47 and the lock spring 63) to slidein the forward/rearward direction with respect to the lower rail 21.

In addition, when the lock release lever 47 is in the lock position, theupper rail 35 is prevented from sliding with respect to the lower rail21 because each lock portion 64 is engaged with the associated lockgroove 25 from below as shown by solid lines in FIGS. 8, 10 and 11. Onthe other hand, rotating the lock release lever 47 down to the unlockposition causes each lock portion 64 which is engaged with some of thelock grooves 25 to be disengaged downward therefrom, which allows theupper rail 35 to slide with respect to the lower rail 21 (see FIG. 9 andimaginary lines shown in FIG. 11).

The left and right pairs of rail units 20 thus assembled are made to beparallel to each other and the positions thereof in the forward/rearwarddirection are made to coincide with each other (the sliding positions ofthe upper rails 35 with respect to the lower rails 21 are also made tocoincide with each other); thereafter, the lower surface of the seatingportion of the seat 11 is mounted on the top surfaces of the upper rails35, and the seating portion of the seat 11 is fixed to the left andright upper rails 35 by a plurality of bolts, not shown in the drawings.

After the left and right rail units 20 and the seat 11 are integrated inthis manner, a loop handle (handle) 70 is connected to the left andright lock release levers 47 using torsion springs (biaser) 76.

The loop handle 70 is a member made by bending a metal pipe having acircular shape in cross section and is provided with a grip portion 71and a pair of rear-end connecting portions 72, wherein the grip portion71 includes a linear portion extending in the leftward/rightwarddirection and a pair of oblique portions extending obliquely rearwardlydownward from both left and right ends of the linear portion while thepair of rear-end connecting portions 72 extend rearward from both leftand right ends of the grip portion 71. Depressed portions are formed onthe lower surfaces of the left and right rear-end connecting portions72, and the top surfaces in the depressed portions are formed as lowercontact surfaces 73. In addition, lock-engaging grooves 74 which arepositioned immediately in front of the lower contact surfaces 73 andextend in the leftward/rightward direction are formed on the lowersurfaces of the rear-end connecting portions 72.

Each torsion spring 76 is a substantially bilaterally-symmetrical membermade by bending a metal wire rod. An upwardly projecting lug 77 isprojected from the rear end of the torsion spring 76, and the front edgeof the torsion spring 76 is formed as a front locking portion 78 whichextends in the leftward/rightward direction. In addition, a lockingprojection 79 which projects upward is projected from the rear end of afront half of a side portion of the torsion spring 76, and a lockingprojection 80 which projects downward is projected from the front end ofa rear half of the side portion.

To connect the loop handle 70 and the torsion springs 76 to the lockrelease levers 47, first the torsion springs 76 are inserted into theconnecting spaces 61 of the left and right lock release levers 47,respectively, the torsion springs 76 are prevented from moving in theforward/rearward direction with respect to the connecting portions 55 byinsertion of the upwardly projecting lugs 77 into the spring lockingholes 54 from below, respectively; furthermore, a middle portion of aside part (the right-hand side part of one torsion spring 76 in the caseof the right torsion spring 76, and the left-hand side part of onetorsion spring 76 in the case of the left torsion spring 76) of onetorsion spring 76 is mounted on the top surface (the rear limit portion60 a) of one rear limit lug 60 (the right-hand side rear limit lug 60 inthe case of the right connecting portion 55, and the left-hand side rearlimit lug 60 in the case of the left connecting portion 55), and thelocking projection 79 of the other side part (the left-hand side part ofone torsion spring 76 in the case of the right torsion spring 76, andthe right-hand side part of one torsion spring 76 in the case of theleft torsion spring 76) is lock-engaged with the rear edge of the otherrear limit lug 60 (the left-hand side rear limit lug 60 in the case ofthe right connecting portion 55, and the right-hand side rear limit lug60 in the case of the left connecting portion 55) from below while thelocking projection 80 of the other side part is lock-engaged with thefront edge of the other rear limit lug 60 from above (see FIGS. 12, 14and 15). Subsequently, the left and right rear-end connecting portions72 of the loop handle 70 are inserted into the left and right connectingspaces 61, respectively, the rear of each rear-end connecting portion 72is inserted into the space between the left and right side parts of theassociated torsion spring 76, and the lock-engaging grooves 74 arelock-engaged with the front locking portions 78.

Upon the slide seat device 10 being assembled by combining the loophandle 70 and the torsion springs 76 with the left and right rail units20, the front of each torsion spring 76 (portions thereof in front ofthe rear limit lugs 60) are resiliently slightly deformed downward bythe rear-end connecting portions 72, and accordingly, an upward biasingforce (elastic force) produced by the front of each torsion spring 76causes the front of each top surface of the rear-end connecting portions72 to come in contact with the front limit portions 56 and causes thelower contact surfaces 73 to come in contact with the rear limitportions 60 a of the rear limit lugs 60 (see FIG. 16). If an occupantmanually holds and rotates the entire loop handle 70 upward by handafter the loop handle 70 is connected to the lock release levers 47 (theconnecting portions 55), this rotational force is exerted on the frontlimit portions 56 and the rear limit portions 60 a from the rear-endconnecting portions 72 to rotate the lock release levers 47 (theconnecting portions 55) upward with the rear-end connecting portions 72,so that the lock release levers 47 in the lock position can be rotatedto the unlock position. On the other hand, rotating the entire loophandle 70 downward causes the left and right rear-end connectingportions 72 to rotate with engaging portions thereof with the frontlocking portions 78 as fulcrums (causes the rears of the rear-endconnecting portions 72 to rotate upward in the rear allowance spaces 59and causes the fronts of the rear-end connecting portions 72 to rotatedownward in the front allowance spaces 57) to move away from the frontlimit portions 56 and the rear limit portions 60 a (see FIG. 17), andtherefore, this rotational force is not transmitted from each rear-endconnecting portion 72 to the associated lock release lever 47 (theconnecting portion 55 thereof) (neither the left or right lock releaselevers 47 rotate).

After fitting the lower halves of the positioning pins P, shown in FIGS.1, 3 and 4, into the positioning holes F2 of the floor board F, thepositioning holes 22 b of the left and right lower rails 21 of the slideseat device 10 are respectively fitted onto the tops of the positioningpins P which project upward from the floor board F, thereby causing thelower surfaces of the spacers 27 that are fixed to the left and rightlower rails 21 to come into contact with upper surfaces of the floorboard F and causes each bolt insertion hole 22 a and each through-hole28 to be positioned immediately above the associated screw hole F1.Accordingly, the slide seat device 10 is fixed to the floor board F ifeach threaded portion 33 is made to be screw-engaged into the associatedscrew hole F1 so that the lower surfaces of the heads 31 of the fixingbolts 30 come into pressing contact with an upper surface of the bottomwall 22.

The left and right upper rails 35 are rearwardly slidable to the rearend position shown in FIG. 2 with respect to the lower rails 21 andslidable forward to the front end position shown in FIG. 1 with respectto the lower rails 21. Although the heads 31 of the front and rearfixing bolts 30 and the middle portions 48 are positioned at the sameheight (the side walls 51 of the middle portions 48 overlap the heads 31in the vertical direction) when the lock release levers 47 are in thelock position as shown in FIG. 5, the entire lock release levers 47 arepositioned between the front and rear fixing bolts 30 (the heads 31thereof) when the upper rails 35 are in the rear end position;therefore, the front and rear heads 31 and the lock release levers 47 donot interfere with each other. On the other hand, even if the lockrelease levers 47 are brought back to the lock position after thepositions of the middle portions 48 and the front heads 31 in theforward/rearward direction are made to coincide with each other bysliding the lock release levers 47 to the front end position, the heads31 of the front fixing bolts 30 are positioned in the receptivedepressed portions 48 a of the middle portions 48 as shown in FIG. 5, sothat the middle portions 48 and the heads 31 do not interfere with eachother. Since the formation of the receptive depressed portions 48 a onthe lock release levers 47 prevents the heads 31 of the fixing bolts 30and the lock release levers 47 from interfering with each other, thelock release levers 47 can be disposed near the bottom walls 22 of thelower rails 21, and hence, a reduction in dimensions of the rail units20 can be achieved.

Since the lower surfaces of the connecting portions 55 are positionedabove the heads 31 even if the lock release levers 47 are brought backto the lock position after the positions of the connecting portions 55and the heads 31 of the front bolts 30 in the forward/rearward directionare made to coincide with each other by sliding the upper rails 35slightly rearward from the front end positions thereof, the heads 31 andthe lock release levers 47 do not interfere with each other in this casealso.

Additionally, even if the metal plate that constitutes a base materialof each lock release lever 47 is thin, the lock release levers 47 canhave a high mechanical strength because each lock release lever 47 hasan inverted U-shaped cross section that includes the pair of side walls51.

Moreover, the lock release levers 47 are prevented from deflecting leftand right with respect to the upper rails 35 by each ridge 47 b and 52 a(portions of the side walls 51) because the ridges 47 b and 52 a, whichare formed on the left and right side walls 51 of the lock releaselevers 47, face inner surfaces of the left and right side wall portions36 b so as to be contactable therewith with minute clearancetherebetween.

Additionally, the rotation support structure for each lock release lever47 with respect to the associated upper rail 35 has a small number ofcomponents and is simple in structure because the upper rails 35 are notprovided with rotational shafts for rotatably supporting the associatedlock release levers 47.

Additionally, the rotation support structure for the loop handle 70 (therear-end connecting portions 72) with respect to the connecting portions55 also has a small number of components and is simple in structurebecause the connecting portions 55 of the lock release levers 47 arealso not provided with rotational shafts for rotatably supporting therear-end connecting portions 72 of the loop handle 70.

In the case where another vehicle collides with the present vehicle, ifthe rear of the right lower rail 21 (the portion thereof which is fixedto the floor board F by one fixing bolt 30) is raised upward whiledeforming the aforementioned portion of the floor board F upward (if therear end of the right lower rail 21 moves higher than the front endthereof), the front of the right lock release lever 47 moves (rotates)lower than the rear thereof, so that this downward moving force istransmitted from the aforementioned lock release lever 47 to the rightrear-end connecting portion 72 of the loop handle 70. Thereupon, theleft rear-end connecting portion 72 moves (rotates) with the rightrear-end connecting portion 72; however, the left rear-end connectingportion 72 rotates downward relative to the left lock release levers 47(the connecting portion 55 thereof), so that the moving force(rotational force) of the left rear-end connecting portion 72 is nottransmitted to the left lock release lever 47. Therefore, the lockedstate of the left rail unit 20 by the left lock spring 63 is maintained,so that the seat 11 (the upper rails 35) does not unexpectedly slidewith respect to the lower rails 21, which is safe.

Although the present invention has been described based on the aboveillustrated embodiment, various modifications can be made to the aboveillustrated embodiment.

For instance, a lock release lever 85 shown in FIGS. 20 through 22 canbe adopted. The lock release lever 85 is in the shape of a substantiallyletter L in cross section and identical in structure to the lock releaselever 47 from which one side wall 51 thereof is omitted. In this casealso, even if the lock release levers 85 are brought back to the lockposition after the positions of the middle portions 48 and the frontheads 31 in the forward/rearward direction are made to coincide witheach other by sliding the lock release levers 85 to the front endposition, the heads 31 of the front fixing bolts 30 are positioned inthe receptive depressed portions 48 a of the middle portions 48 as shownin FIG. 22, so that the middle portions 48 and the heads 31 do notinterfere with each other. Additionally, even if the metal plate that isprovided as a base material of each lock release lever 85 is thin, thelock release levers 85 can have a high mechanical strength because eachlock release lever 85 includes a side wall 51 on either the left orright side.

Additionally, as shown in FIG. 23, a lock release lever 90 in which oneside wall 51 except both front and rear ends thereof are removed can beadopted.

Additionally, as shown in FIG. 24, instead of the ridges 47 b and 52 a,for instance, ribs 47 c (ribs as substitutes for the ridges 52 a are notshown in the drawings) that are substantially semi-cylindrical in shapecan be formed on the left and right side walls 51 of each lock releaselever 47 (or the left and right side walls of the lock release lever 85or 90). The effect of deflecting left and right of the lock releaseslever 47 (85, 90) with respect to the upper rails 35 is further improvedif the ribs 47 c of this kind are made to face inner surfaces of theleft and right side wall portions 36 b of the upper rails 35 so as to becontactable therewith with a minute clearance therebetween.

Additionally, the means for fixing the lower rails 21 to the floor boardF is not limited to the fixing bolts 30; for instance, rivets (notshown) can be used instead. In this case, the lower rails 21 are mountedon a bracket (not shown; which constitutes a part of the floor board F)which is fixed to the floor board F, and the bottom walls 22 of thelower rails 21 and the bracket are fixed to each other by rivets.Thereafter, upon the lock release lever 47, 85 or 90 being brought backto the lock position after the positions of the middle portion 48 andprojections of the rivets (upper ends of the rivets that project upwardfrom the bottom wall 22) in the forward/rearward direction are made tocoincide with each other, the aforementioned projections are to bepositioned in the receptive depressed portion 48 a.

INDUSTRIAL APPLICABILITY

In the slide rail device for vehicle according to the present invention,the rotation support structure for the lock release lever with respectto the upper rail has a small number of components and is simple instructure because the upper rail is not provided with a rotational shaftfor rotatably supporting the lock release lever.

REFERENCE SIGNS LIST

-   10 Slide seat device-   11 Seat-   15 Slide rail device-   20 Rail unit-   21 Lower rail-   22 Bottom wall-   22 a Bolt insertion hole-   22 b Positioning hole-   23 Outer wall portion-   24 Inner wall portion-   25 Lock groove-   27 Spacer-   28 Through-hole-   30 Fixing bolt (fixing member)-   31 Head (projecting portion)-   32 Flange-   33 Threaded portion-   35 Upper rail-   36 Base-   36 a Roof portion-   36 b Side wall portion-   37 Lever accommodating groove-   38 Upright wall-   39 Locking wall-   40 Guide groove-   42 43 Locking lug-   47 Lock release lever-   47 a Rail-incorporated portion-   47 b Ridge-   47 c Rib-   47 d Base wall-   48 Middle portion-   48 a Receptive depressed portion-   49 Narrow-width portion-   50 Rotational contact protrusion (rotational contact portion)-   51 Side wall-   52 Spring-hook groove (first engaging portion)-   52 b Ridge-   53 Lock-spring catching hole (second engaging portion)-   54 Spring locking hole-   55 Connecting portion-   56 Front limit portion (rotation limit portion)-   57 Front allowance space (rotation allowance space)-   58 Depressed portion-   59 Rear allowance space (rotation allowance space)-   60 Rear limit lug-   60 a Rear limit portion (rotation limit portion)-   61 Connecting space-   63 Lock spring (biaser)-   64 Lock portion-   65 Front-end locking lug-   66 Lever pressing portion-   68 Retainer-   69 Bearing ball-   70 Loop handle (handle)-   71 Grip portion-   72 Rear-end connecting portion-   73 Lower contact surface-   74 Lock-engaging groove-   76 Torsion spring (biaser)-   77 Upwardly projecting lug-   78 Front locking portion (locking portion)-   79 80 Locking projection-   85 Lock release lever-   90 Lock release lever-   A Contact portion-   F Floor board-   F1 Screw hole-   F2 Positioning hole-   N Weld nut-   P Positioning pin

The invention claimed is:
 1. A slide rail device for a vehiclecomprising: a lower rail which extends in a forward/rearward direction;an upper rail which is supported by said lower rail to be slidable insaid forward/rearward direction; a locking mechanism which is providedbetween said upper rail and said lower rail and restricts or releases arestriction on sliding of said upper rail; a lock release lever whichswitches said locking mechanism between a slide restriction state and aslide restriction release state by rotating in a vertical direction andincludes a rail-incorporated portion positioned between said upper railand a bottom wall of said lower rail; a rotational contact portion whichis formed on an upper surface of said rail-incorporated portion,contacts a roof surface of said upper rail and rotatably supports saidlock release lever; and a biaser which is installed in saidrail-incorporated portion and said upper rail, said biaser biasing saidrotational contact portion toward said roof surface.
 2. The slide raildevice for a vehicle according to claim 1, wherein said rotationalcontact portion comprises a protrusion which protrudes upward.
 3. Theslide rail device for a vehicle according to claim 1, wherein saidlocking mechanism comprises: a plurality of lock grooves which areformed in said lower rail and aligned in said forward/rearwarddirection; and a lock portion which is engaged in any one of said lockgrooves when said lock release lever is in a lock position and escapesfrom said lock groove when said lock release lever is in an unlockposition.
 4. The slide rail device for a vehicle according to claim 3,wherein said biaser comprises a lock spring including said lock portion.5. The slide rail device for a vehicle according to claim 1, whereinsaid biaser comprises a torsion spring, wherein said torsion springprevents said lock release lever from moving forward and rearwardrelative to said upper rail.
 6. The slide rail device for a vehicleaccording to claim 5, wherein said torsion spring comprises a lockportion which is engaged in any one of a plurality of lock groovesformed in said lower rail to be aligned in said forward/rearwarddirection when said lock release lever is positioned in a lock position,and said lock portions which escapes from said lock groove when saidlock release lever is positioned in an unlock position, and wherein saidlock release lever includes a first engaging portion which is engagedwith said torsion spring at a portion in the vicinity of said lockportion and a second engaging portion which is engaged with said torsionspring at a portion thereof which deviates from said first engagingportion in said forward/rearward direction.
 7. The slide rail device forvehicle according to claim 1, wherein a portion of saidrail-incorporated portion is formed as a narrow-width portion which issmaller in width than the surrounding portion of said rail-incorporatedportion, and wherein at least part of said biaser is positioned in aspace formed between said upper rail and both sides of said narrow-widthportion.